1. Field
This invention relates generally to wireless receivers and more particularly to wireless receivers configured, at least in part, as an integrated circuit.
2. Related Art
Wireless receivers of various kinds are known in the art including a variety of receivers that are realized, wholly or partially, as an integrated circuit. There are, however, at least some application settings where existing approaches in this regard are viewed as requiring, for example, too much space on the integrated circuit. This, in turn, can stymie product designers who, for any number of reasons, seek a receiver having a smaller platform footprint.
Consider, for example, a wireless receiver having a radio frequency (RF) front end comprising a low-noise transconductor (such as a voltage-to-current converter) that drives a switching mixer to thereby yield a baseband (or low intermediate frequency) output in the current domain. A following transimpedance amplifier (such as a current-to-voltage converter) can then receive that output and convert the result into the voltage domain. In order to maintain a differential voltage as this output, the components as comprise these elements must themselves be fully differential. In the past, this has necessitated the use of feedback paths (one for each side of the differential output) that each include a capacitor (that is, the feedback path flows through the capacitor). Capacitors, of course, often comprise one of the larger components to successfully form in an integrated circuit and hence contribute greatly to the overall resultant size of the receiver.
Eliminating one or both of these capacitors to reduce the size of the receiver poses numerous design challenges. It is important, for example, that the solution not unduly impact the performance of the aforementioned low-noise transconductor or the switching mixer. It is also important that the component area at issue present a low impedance to the switching mixer. These and numerous other problems have generally frustrated the development of suitable solutions in this application setting.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention. It will further be appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used herein have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study except where specific meanings have otherwise been set forth herein.